A Closed-End Manometer Was Constructed from a U-Shaped Glass Tube

A closed-end manometer was constructed from a U-shaped glass tube. It was loaded with mercury so that the closed side was filled all the way to the top, which was 800 mm above the neck, while the open end was at a level 180 mm above the neck. The manometer was taken into a chamber used for training astronauts. What is the highest pressure that can be read with assurance on this manometer?

A) 62.0 torr
B) 62.5 torr
C) 980 torr
D) 98.5 torr
E) 620 torr